The First Total Synthesis of (±)-γ-Herbertenol, a Herbertene Isolated from a Non-Herbertus Source

Abstract

The structure of the aromatic sesquiterpene, (±)-γ-herbertenol, the first herbertane to be isolated from a non-herbertus source, was confirmed by a total synthesis, employing a Claisen rearrangement and ring-closing metathesis.

Key words

natural products - total synthesis - rearrangement - ring closure - metathesis

References

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  It is worth noting that the structures of two sesquiterpenes HM-2 and HM-3, isolated from the phytopathogenic fungus Helicobasidium mompa, [13a] were assigned as herbertenoids. However, recently the structures were revised as cuparenoids by total synthesis. [13b] [c]

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8

Attempts at converting the bromide 25 into the aldehyde 27 using the Kornblum oxidation gave a mixture of the aldehyde 27 and the alcohol 26.